Pivot pin or bolt



Dec. 8, 1953 w. R. PETERSEN PIVOT PIN oa BOLT Filed March 26, 1949 HlllINVENToR. War/"en /Dezersen A TTORNE Y.

Patented Dec. 8, 19573 UNITED STATES PATENT OFFICE Warren R. Petersen,Baldwin, N. Y.; assigner to Republic Aviation Corporation, near Farmingdale, N. Y., a corporationof Delaware Application Mardi .26, 1949,serial no. catto 1 Claim.

heretofore used in the connection of structural elements or thecomponents of linkage systems and elsewhere but is distinguished inthatitl be quickly and easily inserted or placed in its Operativeposition and be as quickly removed.

The present pin or bolt is especially useful in the connection of partsor structural components in locations where the space surrounding thecomponents or parts is restricted or limited, since this devicelrequires no tools for its connection or disconnection and may, ifnecessary, be posi` tioned for attachment or removed from attache mentby and with one hand only. Incidental to the attachment or removal ofthe instant lbolt or pin it may be tightened or loosened, as desired,with respect to the parts or components which it connects or secureswithout requiring the use of more than one hand for either adjustment orthe employment of tools.

Moreover, regardless of whether the pin or bolt is tightened or is loosein its operative position;

its accidental displacement is virtually' impossible and it can be andis maintained in its oplei-ative position by the inherent features andcharacteristics of the bolt or pin without the 's'e of lock nuts,Washers, safety wire, and the'like'.-

With the above and other objects in view as will be apparent, thisinvention consists of the plerits of the' .bolt or pill assemblyafter"its"` sertion through the overlapping endsl ofhthe' con;

nected links or' levers and before the tightening thereof; i

Fig. 3 is' a` View like Fig. 2 illustrating the" rela-V tive` positionsof thev components of the bolt or pin` assembly after the tighteningthereof;l

Fig. 4 is a transversel section taken along line 4-6' of Fig. 2 to showthe spring in c-onjunction with the shank and the means byr whichr itsYends and anchoredv or secured; and

Fig. 5 is" a fragmentary' longitudinal vs'otioii' through 'a Somewhatldied form f the present invention.

The' instant pivot pin or bolt is of general adaptation andi use in theconnection or associationof coasting elements of operating or controlsystems or in the connection or attachment of structural components-However, it is particularly useful in the pivotal connection of thecoacting elements of the control systems of airplanes, and also can beemployed the attachment of Structuralcoifnpoients of aircr'aftf,especially where the space available for the attachment, adjustment andremoval of devices of this character is restricted or limited.

Prior t'o the present invention it has been euse t-omary to pivotallyconnect the' links, levers or other' components of e aircraftI controlsystems", such as the' links or levers of a system for the adjustment ofmovable control surfaces, by bolts or equivalent devices'l. Where boltshave been uses for this' fairnessY it necessarily follows that? the bolt-be held stationary while a nut is threaded home thereon. This obviouslyrequitesV the use of bothhands of the mechanic and freiuentlyinsufficient space is available at and near the point 'of connection forthese two oper-ations. Furth'errhore,4 safety requires that, once thenut is fully adjusted o-ithe bolt, it be locked iriits operativeposition against retrograde movemerit due" t'o vibration and othercauses. Therefore', lo`cknuts, lool; washers and similar deviceshavebeen used'` with not' too satisfactory results. Since these lockingdevices" have not always been entirely successful in overcoming anylretrograde movement of the' uniti safety"Y wire has been commonly usedaircraft construction. This requres the creation` oian aperture orapertures in then' nut normal to the axis of the bolt through whichsafety wire may be" threaded with its ends attached to some Xed orstationary part of the airplane; Another expedient frequently resortedto is' to lock? the' nut against displacement or movltri the bo1t-,-W`tha Cotter pin. Regarde' 1eS"S "'fthe means heretofore employed to locl ain placing them in, or removing them from, their operative position; andfourth, the expense en tailed both in the initial cost of conventionalsafety locks and devices and in the replacement thereof after removal.In the latter instance it is frequently necessary, once a pivot bolt orpin of the character heretofore common, has been removed, to replace itwith an entirely new bolt and associated parts.

rllhe present invention overcomes most, if not al1, of the objectionablecharacteristics of these prior devices by providing a unitary assemblywhich may be placed in or removed from its operative position by onehand of the mechanic and without the use of tools. It is also possible,with the instant invention, to provide a pvot pin or bolt that, oncehaving been placed in its operative position, will remain in position,regardless of conditions and of whether it is loose or tight, until itis intentionally removed. Moreover, the present bolt or pivot pin may berapidly removed and reinserted in its operative position without thedestruction or replacement of any of its parts.

In short the present invention provides a pivot pin or bolt which cannotbe displaced or loosened by vibration, may be inserted and removedrepeatedly without damage and by only one hand of the mechanic andfinally, if by chance, it becomes loose, or is by mistake leftuntightened, in its operative position, will remain in place performingall of its functions until intentionally removed.

In the drawing, which illustrates only one of the many uses of thepresent device, i8 designates a link or lever comprising one element ofan airplane control system. Complemental to and to cooperate with thelink or lever It is a second link or lever li. The adjoining terminalsof the levers it and il are to overlap and are respectively providedwith the transverse apertures l2 and i3 which, when in registration, mayreceive a pivot pin or bolt like those heretofore used or one made inaccordance with the present invention. The nature and construction ofthe levers or links lil and il and the arrangement of the apertures l2and i3 piercing the extremities thereof can be accepted as conventionaland per se form no part of the present invention.

The shank iiiof the instant bolt or pin has a threaded end portion itand preferably ,has an elongated slot it piercing that threaded endportion. This slot iii may, in the alternative, comprise a bifurcationextending through the extremity of the shank it, though it has beenfound to be better practice to have the slot closed at its outer end asillustrated. The threads of the end portion it of the shank iii, slottedas aforesaid, extend inwardly of the shank somewhat beyond the inner endof the slot i5.

At its opposite end the shank i4 is bifurcated to create a pair ofspaced, parallel arms Il between which a latch i3 is pivoted medially ofits length, as at it. This latch i3 is pointed as at IE at its outerextremity to facilitate its insertion in the registered openings i2 andI3 in links l and il and is slightly curved at its inner extremity i8 sothat it may swing freely between the arms. When the latch i8 is alignedwith the shank ill, as shown in Fig. l, it constitutes an extensionthereof. In other Words the latch iii has a maximum width substantiallyequal to the diameter of the shank Hl and has a length which exceeds therespective diameters of the apertures l2 and I3, for the purpose to behereinafter mor fully described.

A nut 2li is threaded on the extremity i6 of the shank id and its outeredge surface may be knurled to facilitate the rotation thereof on theshank lli. The outer face of the unit 2S is provided with a cavity orcup ai and as will be seen from Figs. 2 and 3 the threaded end portionl5 of the shank le may project into and on occasion traverse this cup orcavity. Prior to tightening of the assembly in its operative position(Fig. 2) the threaded extremity of the shank terminates approximately atthe bottom of the cavity 2l and after the assembly is tightened in itsoperative position (Fig. 3), the outer extremity of the threaded portionlli of the shank ifi is substantially in the plane of the outer face ofthe nut it. To prevent the nut 2li from ever becoming separated from thethreaded extremity It of the shank Hl, the outer extremity of the shankis enlarged or upset, as at 22, to create a head which will arrest themovement of the nut 2i) outwardly on the threaded extremity i6 of theshank lli prior to disengagement of the shank it thereby.

A helical spring 23 enciroleg7 the shank Hi between the latch i3 and thethreaded extremity It thereof. Gne end 23' of this spring is bentlaterally to be inserted in and permanently engaged by the slot i5 ofthe shank ifi. Thus the spring for all practical purposes becomes onewith the shank Eri by having one of its ends engaged by one end of theshank. A Washer 2.1i is loosely positioned on the shank i4 between theend 2S of the spring 23 and the inner face of the nut 2i! to act merelyas an abutment for that end of the spring. lt is manifest that not onlyis one end Z3' of the spring attached to the shank, but that the bodilymovement of the spring relative to the shank i-i is limited by thelength of the slot l5. The opposite end 23 of the spring is riveted orotherwise attached, as at 25, to a somewhat larger washer 25 looselymounted upon the shank i4.

With the washers 2d and :25 mounted on the shank ifi and the spring 23interposed between them, with one end 23 seated in the slot i5 and theother end 23 fixedly secured to the washer 26, the entire assembly is aunit wherein the several components are, for all practical purposes,inseparable. By this means the present invention does away with anygathering and assembling of components of a connector just prior to orconcurrently with use.

With the device assembled as aforesaid and with the nut 2li at the outerlimit of its path of movement on the threaded end portion i5 of theshank lll, e., with head 22 abutting the bottom of the cavity or cup 2i,the thumb of one hand may be placed on the outer surface of the nut andthe washer 25 may be engaged by the first or second ngers or both of thesame hand, whereupon the spring may be compressed between the nut 2liand the washer 2E. The pointed end it of the latch id is then insertedin the registered openings i2 and I3 of the links or levers it and Iluntil the inner end le of the latch is is free of these openings, afterwhich the latch is moved on its pivot i9 to rest at right angles to theaxis of the shank ifi and to project upon both sides thereof as shown inFigs. 2, 3, and 5. Thereupon the release of the pressure on the nut 2@and washer 2t permits the spring 23 to expand and draw the angularlydisposed latch I3 into contact with the outer surface of the adjacentlever or link. At this time the overlapping ends of the links or leverslo and H are pivotally secured together and the shank I4 cannot, keitherunintentionally or accidentally, be

removed from the openings or apertures I2 and I3 because the action ofthe spring 23 and the pressure developed thereby upon the links betweenthe latch I8 on one side and the washer 26 on the other side of theconnection prevents any displacement of said latch, from its operativeposition. This condition of the assembly priortO tightening is disclosedin Fig. 2, and it may be said that the connection thus establishedbetween the levers I8 and I I, while substantial and secure, is loose orsomewhat sloppyf With the device as shown in Fig. 2, the nut 26 may bethreaded downwardly on the shank I4 until the spring k2? issubstantially fully compressed and the coils thereof 'rest approximatelyone upon the other (see Fig. 3). This tightens the entire joint andeliminates any play therein and securely locates and locks the pin orbolt in its operative position.

No provision is made to counteract any retro grade movement of the nut26 since if the nut 26 threads outwardly on the shank I4, for anyreason, this outward movement is arrested if and when the head or upsetterminal extremity 22 of the shank I4 contacts or engages the bottom ofthe cup or cavity 2I in the nut. The only way in which the device can beremoved fromv the apertures I2 and I3 to sever the connection betweenthe links I3 and I2 is to iirst thread the nut 2t outwardly on the shankI4 until its elements assume the position shown in Fig. 2, whereupon thespring 23 may be compressed between the nut 2s and the washer 26 topermit reciprocation of the shank in said openings and thereby move thelatch I8 away from the surface of the adjacent lever or link. Thecontinuation of this movement frees the latch I8 for pivotal movementbetween the arms I'I so that it may assume a position in alignment withor coextensive of the shank I4, as shown in Fig. 1. The entire device orassembly then may be removed from cooperation with the links or leversby withdrawing the shank I 4 from the openings I2 and I3. 'I'heinsertion and removal of the subject device obviously can be repeatedendlessly without damage to the assembly or the separation and loss ofany of its elements.

When the components of the pivot pin or nut assembly are positioned asshown in Fig. 2 the nut 26, as above pointed out, is to be threadedinwardly on the shank I4 to tighten the joint or reversely, when theyare positioned as shown in Fig. 3, the' nut 28 is to be threadedoutwardly on the shank I4 to loosen or free the joint. To facilitateeither of these threading operations by preventing rotary movement ofthe shank I4 within the openings I2 and I3, a peg or other suitableprojection or stop 2l is fixed to and projects from the lever or linkcoacting with the latch I8 and is so positioned that it will contact orabut the latch as and if it rotates in either direction. Hence,regardless of the direction of rotation of the nut 26 and the similarrotation of the shank I 4, the maximum rotation permitted isapproximately 360 when contact is established by the latch with the pegor stop 2l. Once this contact is established the rotation of the shankand latch is arrested, and the nut 26 may continue rotating in the samedirection without imparting any further rotary movement to the shank I4and latch I8. In this manner the shank is held xed against rotarymovement whether the joint or connection is being tightened or 6loosenedand'without the use of any tool or tools' for that purpose.

InFig. 5 is shown a modication of the bolt or pivot pin assemblyillustrated in Figs. 1-4 inclusive. In this form of the invention aportion of the length of the shank I4 is reduced in diameter, as at I4', to create a circumferential shoulder I4 on the shank medially of itsends. The outer extremity I5 of the reduced portion I 4 of the shank isthreaded and is provided with the head or upset 22 at its outerextremity in the same manner and for the same purpose as in Figs. 1 to4, so that the nut 26 is, for all practical purposes, permanentlysecuredto the reduced portion I4 of the shank] In this embodiment of the`invention a cup washer' 28 is disposed adjacent the inner surface ofthe nut 23. The cavity of this cup washer 28 faces away from the nut 26so that its bottom rests iiush against the inner face of the nut 2i);its cavity or cup may receive andY house one end of the spring 23. Inopposition to the cup washer 28 with respect to the spring 23 is thewasher 26- which encircles the reduced portion I4 of the shank I4 andnormally bears against the shoulder' I4 of the shank. A concentricspacer 23 is provided for cooperation with the washer 26 and may beformed integrally on the face thereof opposed to the shoulder I4" toclosely encircle and reciprocate onvthe reduced portion I4' of theshank. The coil spring 23 encircles' the reduced portion I4 of the shankas well as the spacer 29 and at one end thereof is seated in the cavityof the cup washer 28 and at its opposite end is in abutting contact withthe face of the Washer 26. This spring vmaintains the normal contactbetween the washer 26 and the shoulder I4" of the shank I4.

The operation of the modified device shown in Fig. 5 is identical withthe operation of the form illustrated in Figs. 1 to 4 inclusive. The nut20 is threaded outwardly on the reduced portion I4 of the shankwhereupon the compression of the spring 23 is relaxed to be againcompressed by pressure exerted between the nut 20 and the washer 26 tothe end that the latch I8 may be aligned with the shank I4 and theassembly unit may be inserted in or removed from the registered openingsI2 and I3. By threading the nut 20 inwardly of the reduced portion I4 ofthe shank I4 after the insertion of the latter in the openings `I2 andI3 the spring 23 is compressed between the washer 26 and the nut 26 totighten the joint or connection established by the unit or assembly.Regardless of whether the nut 26 is threaded inwardly or outwardly ofthe reduced portion I4' of the shank I4 the spacer 29 associated withthe washer 26 can, even if stationary on the shank, have telescopiccooperation with the spring 23. When the spring 23 is as fullycompressed as desired between the nut 2B and associated cup washer 28and the washer 26, the spacer 29 telescopes with the cavity of thewasher 28 and by its contact with the bottom of the washer arrests anyfurther compression of the spring 23 so that this spring can never besaid to be over-compressed.

From the foregoing it is manifest that the present unitary bolt or pivotpin, in Figs. 1 to 4 inclusive, consisting of the shank I4, the latchI8, nut 2l), washers 24 and 26 and the spring 23 intelposed between themand permanently secured at its ends respectively to the shank I4and'washer 26, and in Fig. 5 of the shank I4 having one end portion I4reduced and threaded, the latch I8, nut 26, washers 26 and 28, spacer 29either integral with or merely abutting the washer 26, and the spring 23disposed between the washers 26 and 2t, comprises one assembly whereinthe enumerated components or elements are, in effect, permanentlyassociated one with the other` and cannot under normal conditions,become separated. Moreover, the spring 23 of the unit may always becompressed and the outward movement of the nut 2E) arrested with onehand only, and at the same time and with the same hand the latch i8 maybe either aligned with the shank I4 or be placed at right angles theretoby one nger of the same hand.

Furthermore, it is evident that if the joint is relativeiy loose asdisclosed in Fig. 2, the pin or bolt assembly cannot be dislodged orremoved from the openings l2 and I3 without first compressing the spring23 and positioning the latch IS in alignment with and coextensive of theshank lli as it is illustrated in Fig. 1.

What is claimed is:

A pivot pin or bolt comprising a shank for insertion in registeredopenings in a pair of members to be joined thereby, said shank havingone end portion thereof reduced to establish a shoulder between saidreduced end portion and the remainder of said shank, threads on saidreduced portion extending inwardly from the extremity thereof, a nutcoacting with said threads, means at the extremity of said reducedportion to prevent the removal of said nut, first and second washersloosely mounted on said reduced portion, said rst washer adapted tonormally rest against said shoulder and said second washer against theinner face of said nut, a spacer loosely mounted on said reduced portionbetween said first and second Washers, a spring encircling said reducedportion between said rst and second washers. a latch pivoted t0 the endof said shank opposed to said reduced portion to rest either in aninoperative position coextensive with said shank or in an operativeposition at right angles thereto to bear against the adjacent surface ofone of the members, and a projection secured to and projecting outwardlyfrom the surface of the member coacting with said latch to project intothe path of rotary movement thereof when in its operative position toarrest such rotary movement, said nut effective upon rotation in onedirection on said reduced portion to move said second washer toward saidfirst washer to compress said spring therebetween, said spacer effectiveupon such rotation to permit the full compression of said spring and toprevent the over compression thereof, and the distance between saidlatch and shoulder of said shank being less than the combinedthicknesses of the members.

WARREN R. PETERSEN.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 161,752 Carleton Apr. 6, 1875 556,127 'Wrigley Apr. 7, 1891743,2ll Alexander Nov. 3, 1903,

1,540,735 lreir June 2, 1925 2,318,548 Whitehead et al. May 4, 19432,398,644 Johnson Apr. 16, 1946 FOREIGN PATENTS Number Country Date452,358 Great Britain Aug. 20, 1935

